مسند أحمد

It was narrated from `Ali (رضي الله عنه) that Fatimah came to the Prophet (ﷺ) to ask him for a servant. He said: “Shall I not tell you of something that is better for you than that? Say Subhanallah thirty-three times, Allahu Akbar thirty-three times and Alhamdulillah thirty-three times; one of them thirty-four times.`